/* Copyright 2012 Jun Wako <wakojun@gmail.com> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "hal.h" #include "led_custom.h" #include "rev6.h" #include "printf.h" static void breathing_callback(PWMDriver *pwmp); static PWMConfig pwmCFG = { 0xFFFF, /* PWM clock frequency */ 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */ NULL, /* No Callback */ { {PWM_OUTPUT_DISABLED, NULL}, {PWM_OUTPUT_DISABLED, NULL}, {PWM_OUTPUT_ACTIVE_HIGH, NULL}, /* Enable Channel 3 */ {PWM_OUTPUT_DISABLED, NULL} }, 0, /* HW dependent part.*/ 0 }; static PWMConfig pwmCFG_breathing = { 0xFFFF, /* 10kHz PWM clock frequency */ 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */ breathing_callback, /* Breathing Callback */ { {PWM_OUTPUT_DISABLED, NULL}, {PWM_OUTPUT_DISABLED, NULL}, {PWM_OUTPUT_ACTIVE_HIGH, NULL}, /* Enable Channel 3 */ {PWM_OUTPUT_DISABLED, NULL} }, 0, /* HW dependent part.*/ 0 }; // See http://jared.geek.nz/2013/feb/linear-led-pwm static uint16_t cie_lightness(uint16_t v) { if (v <= 5243) // if below 8% of max return v / 9; // same as dividing by 900% else { uint32_t y = (((uint32_t)v + 10486) << 8) / (10486 + 0xFFFFUL); // add 16% of max and compare // to get a useful result with integer division, we shift left in the expression above // and revert what we've done again after squaring. y = y * y * y >> 8; if (y > 0xFFFFUL) // prevent overflow return 0xFFFFU; else return (uint16_t)y; } } void backlight_init_ports(void) { palSetPadMode(GPIOB, 8, PAL_MODE_ALTERNATE(2)); pwmStart(&PWMD4, &pwmCFG); if (kb_backlight_config.enable) { if (kb_backlight_config.breathing) { breathing_enable(); } else { backlight_set(kb_backlight_config.level); } } else { backlight_set(0); } } void backlight_set(uint8_t level) { uint32_t duty = (uint32_t)(cie_lightness(0xFFFF * (uint32_t)level / BACKLIGHT_LEVELS)); if (level == 0) { // Turn backlight off // Disable channel 3 on PWM4 pwmDisableChannel(&PWMD4, 2); } else { // Turn backlight on if (!is_breathing()) { // Enable channel 3 on PWM4 pwmEnableChannel(&PWMD4, 2, PWM_FRACTION_TO_WIDTH(&PWMD4, 0xFFFF, duty)); } } } uint8_t backlight_tick = 0; void backlight_task(void) { } #define BREATHING_NO_HALT 0 #define BREATHING_HALT_OFF 1 #define BREATHING_HALT_ON 2 #define BREATHING_STEPS 128 static uint8_t breathing_period = BREATHING_PERIOD; static uint8_t breathing_halt = BREATHING_NO_HALT; static uint16_t breathing_counter = 0; bool is_breathing(void) { return PWMD4.config == &pwmCFG_breathing; } #define breathing_min() do {breathing_counter = 0;} while (0) #define breathing_max() do {breathing_counter = breathing_period * 256 / 2;} while (0) void breathing_interrupt_enable(void){ pwmStop(&PWMD4); pwmStart(&PWMD4, &pwmCFG_breathing); chSysLockFromISR(); pwmEnablePeriodicNotification(&PWMD4); pwmEnableChannelI( &PWMD4, 2, PWM_FRACTION_TO_WIDTH( &PWMD4, 0xFFFF, 0xFFFF ) ); chSysUnlockFromISR(); } void breathing_interrupt_disable(void){ pwmStop(&PWMD4); pwmStart(&PWMD4, &pwmCFG); } void breathing_enable(void) { breathing_counter = 0; breathing_halt = BREATHING_NO_HALT; breathing_interrupt_enable(); } void breathing_pulse(void) { if (kb_backlight_config.level == 0) breathing_min(); else breathing_max(); breathing_halt = BREATHING_HALT_ON; breathing_interrupt_enable(); } void breathing_disable(void) { breathing_interrupt_disable(); // Restore backlight level backlight_set(kb_backlight_config.level); } void breathing_self_disable(void) { if (kb_backlight_config.level == 0) breathing_halt = BREATHING_HALT_OFF; else breathing_halt = BREATHING_HALT_ON; } void breathing_toggle(void) { if (is_breathing()){ breathing_disable(); } else { breathing_enable(); } } void breathing_period_set(uint8_t value) { if (!value) value = 1; breathing_period = value; } void breathing_period_default(void) { breathing_period_set(BREATHING_PERIOD); } void breathing_period_inc(void) { breathing_period_set(breathing_period+1); } void breathing_period_dec(void) { breathing_period_set(breathing_period-1); } /* To generate breathing curve in python: * from math import sin, pi; [int(sin(x/128.0*pi)**4*255) for x in range(128)] */ static const uint8_t breathing_table[BREATHING_STEPS] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 17, 20, 24, 28, 32, 36, 41, 46, 51, 57, 63, 70, 76, 83, 91, 98, 106, 113, 121, 129, 138, 146, 154, 162, 170, 178, 185, 193, 200, 207, 213, 220, 225, 231, 235, 240, 244, 247, 250, 252, 253, 254, 255, 254, 253, 252, 250, 247, 244, 240, 235, 231, 225, 220, 213, 207, 200, 193, 185, 178, 170, 162, 154, 146, 138, 129, 121, 113, 106, 98, 91, 83, 76, 70, 63, 57, 51, 46, 41, 36, 32, 28, 24, 20, 17, 15, 12, 10, 8, 6, 5, 4, 3, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; // Use this before the cie_lightness function. static inline uint16_t scale_backlight(uint16_t v) { return v / BACKLIGHT_LEVELS * kb_backlight_config.level; } static void breathing_callback(PWMDriver *pwmp) { (void)pwmp; uint16_t interval = (uint16_t) breathing_period * 256 / BREATHING_STEPS; // resetting after one period to prevent ugly reset at overflow. breathing_counter = (breathing_counter + 1) % (breathing_period * 256); uint8_t index = breathing_counter / interval % BREATHING_STEPS; if (((breathing_halt == BREATHING_HALT_ON) && (index == BREATHING_STEPS / 2)) || ((breathing_halt == BREATHING_HALT_OFF) && (index == BREATHING_STEPS - 1))) { breathing_interrupt_disable(); } uint32_t duty = cie_lightness(scale_backlight(breathing_table[index] * 256)); chSysLockFromISR(); pwmEnableChannelI( &PWMD4, 2, PWM_FRACTION_TO_WIDTH( &PWMD4, 0xFFFF, duty ) ); chSysUnlockFromISR(); }